1. Field of the Invention
The present invention relates to an image forming device. The present invention further relates to a toner delivery mechanism, and more specifically to a toner delivery mechanism used in an image forming device such as a copying machine, printer, facsimile, and so forth of a type that transfers an applied toner image to recording paper.
2. Background Information
An image forming device that develops an electrostatic latent image into a toner image and transfers the applied toner image to recording paper comprises an image forming means in a predetermined location within a housing. The image forming means normally comprises a developing device and a cleaning device in addition to a photoreceptor acting as an image carrier means. The electrostatic latent image is formed on the image carrier means through an appropriate method, and the applied electrostatic latent image is developed into a toner image by the operation of the developing device. Next, the toner image is transferred to a recording sheet such as a standard paper sheet, and the residual toner on the image carrier means is removed thereafter by the operation of the cleaning device.
The cleaning device generally has a toner collection receptacle attached through a toner delivery mechanism, where the toner removed from the image carrier means can be collected into a toner collection receptacle after being delivered by the toner delivery mechanism. The toner delivery mechanism is constructed from, for instance, a long and thin collection pipe that extends to deliver toner from the cleaning device to the toner collection receptacle, and a collection spiral consisting of metal coil members that extend within the collection spiral and rotate.
When a sufficient amount of toner is not in the collection pipe with this type of toner delivery mechanism, a very loud noise is generated by the collection spiral scraping against the inner wall surface of the collection pipe when the collection spiral extended within the collection pipe is rotated. This noise is reduced when a sufficient amount of toner is in the collection pipe, with the toner functioning as a lubricating agent.
The conventional counter to this calls for forming the collection spiral from, for example, synthetic rubber with a hardness of 50 to 70 on the type A hardness test using a spring regulated to Japanese Industrial Standard JIS-K-630 (see Japanese Patent Application Publication No. 2002-14587).
According to the construction described in the above publication, forming the collection spiral from synthetic rubber is preferred in order to sufficiently control the generation of noise, even before sending a sufficient amount of toner into the collection pipe.
However, according to the construction described in the above publication, the collection spiral cannot avoid always being in contact with the same part of the inner wall surface of the collection pipe when rotating, regardless of whether there is toner in the collection pipe. More specifically, if a portion of the collection pipe is curved, that portion of the collection pipe may become damaged through extended use when the collection spiral contacts with the same part of the inner wall surface at the curved portion when rotating.